This invention relates generally to thermoset composite structural materials and, more particularly, to thermoset sandwich structures for thermal management and passive damping applications. Thermoset composite sandwich structures are common. They typically have a relatively thick core material surrounded by face skins of much thinner material. The core material generally provides a rigid matrix. The face skins provide structural reinforcement and typically include high modulus fibers or graphite or similar materials in a resin base, to provide rigidity in selected directions, and high thermal conductivity. Thermoset composite panels may be used as thermally conductive panels on spacecraft, or as structural materials in a variety of applications.
Unfortunately, although structures of this type have desirable strength and lightness of weight, they are almost completely non-compliant once they have been processed at elevated temperatures and "cured." The rigid matrix locks the structures in a final shape that is typically determined by a mold in which they are fabricated. Complex shapes have to be fabricated using appropriately shaped molds or tools, the use of which, of course, increases the cost of the structures. Applying heat and pressure to a cured thermoset sandwich structure to adjust its shape has only a limited effect, at best, and may result in damage to the structure caused by mechanical failure of the matrix. Moreover, non-compliant structural members may need active and passive damping for use on spacecraft.
There is a need for thermoset sandwich structures that have high thermal conductivity, but still exhibit compliant behavior that permits modification of the structural profile after curing, and avoids or reduces the need for active or passive damping. The present invention satisfies this need.